Based on the generalized model test,we measure the flow velocity around the root of the spur dike under the flow-deflecting reef and analyze the flow velocity value around the root of spur dike under different conditions,and obtain the velocity distribution pattern around the dike root under different flow volumes and different water depths.The analysis shows that under the influence reef,the flow velocity near the dike root is much higher than that of the normal reach,and the velocity of the cross section and profile near the dike root increases with the increasing flow and decreases with the increasing water depth.